1. Field of the Invention
The present invention relates generally to a method and system for recycling paper products and other recyclable cellulosic materials, and more specifically to a method and system for producing animal bedding from waste paper products such as old newsprint by shredding and fiberizing the waste paper stock and then treating the fiberized paper with additives which may include: pesticides, disease immune additives (medicines), ammonia inhibitors, fire retardants and other materials, depending upon the specific application and desired characteristics of the final product.
2. Description of Related Art
Discarded paper products make up approximately thirty-eight percent of the total waste stream. With available landfill space decreasing, recycling of paper products has become necessary. It has been found that a variety of useful products may be manufactured from recycled paper products. This has the dual benefit of reducing the volume of waste which must be landfilled, and enabling the production of a variety of useful materials at a relatively low raw material cost.
Paper waste, such as old newsprint can be recycled by known recycling techniques to produce a variety of products, including building insulation, animal bedding, soil amendment mulch, spill absorbents, boiler fuel pellets and packaging materials
Low-density cellulose insulation can be made from paper fibers obtained from most types of bulk waste paper stock. The most common type of bulk waste paper stock used for insulation is old newsprint. To make cellulose insulation from newsprint, the newsprint is shredded and fiberized prior to being mixed with a fire retardant chemical. Air cells within the shredded paper make the product lightweight and provide the thermal resistance necessary to make a high quality building insulation. Other chemical additives may be introduced to the insulation product, such as pesticides, moisture inhibitors, and/or colorants.
Waste paper stock can also be recycled to produce soil amendment mulch for soil conditioning, erosion control or seedling protection. The paper is shredded or chipped, and additives are introduced to fertilize the soil, resist or accelerate decomposition, provide products of different colors and provide pesticides.
Waste paper can also be recycled to produce a spill absorbent material for cleaning up liquid spills. Additives can be provided to spill absorbents which improve the absorbency of the product, resist flammability and neutralize a variety of chemicals. Boiler fuel pellets and packing materials can also be produced from recycled paper waste.
Because of the different characteristics required for each application, the methods of producing each of these products vary greatly, as do the products themselves. For example, a variety of additives can be provided along with the recycled paper base material, to impart characteristics desirable for the specific application.
In the field of animal bedding, for example, it has been found desirable to introduce additives including pesticides, disease immune additives (medicines), ammonia inhibitors and fire retardants. Providing the bedding with pesticides and disease immune additives protects the health of the animals using the bedding. Ammonia inhibitors help to control fumes and odors caused by animal waste, thereby reducing the ventilation necessary. This reduces the expense of electricity used to run the ventilating fans in the animal pens, and also reduces heating expenses, as less heat is lost through the ventilation exhaust. It has also been found desirable to provide a bedding material having higher thermal insulative properties than known bedding materials, thereby also helping to reduce heating expenses.
Known bedding materials and known methods of producing these materials have been found to be less than adequate in use. For example, commonly used bedding materials such as wood shavings and sawdust do not provide good thermal insulation, and are flammable. Also, these materials are increasingly used for other applications, such as producing "particle board" building materials, fuels, and for other uses. This has resulted in increased costs and decreased availability.
These known bedding materials also lack the pesticidal, disease-inhibiting and ammonia-inhibiting characteristics which have been found desirable, and may, in fact, promote the proliferation of pests and disease. In the past, in order to provide known bedding materials such as wood shavings and sawdust with pesticidal and disease inhibiting qualities, it has been necessary to first lay down the bedding material, next spray the bedding with a medicinal disease inhibitor, and finally, spread a pesticide over the bedding. This three step process is labor-intensive and results in substantial down-time for the facility.
Previous attempts to use recycled paper waste as animal bedding have proved less than successful. Simple shredded paper has been found to be less than entirely satisfactory as a bedding material, as it lacks sufficient absorbency and thermal insulating capacity. This is primarily due to the fact that shredded paper tends to compress, or lie flat when used. Because normal shredded paper does not "loft," it does not provide good surface coverage (i.e., low surface area covered per unit weight). It has also been found that chemical additives do not adhere to the surfaces of simple shredded paper as well as would be desired, and that the material does not decompose as readily as would be desired.
Thus, it has been found that a need exists for a method and system of producing an animal bedding from recycled waste paper products, which enables the addition of various additives to the recycled paper product, thereby permitting the product's characteristics to meet a variety of requirements.
For example, it has been found that a need exists for a method and system for producing an animal bedding product with additives to provide fire resistance, to help control insects and rodents, to deliver disease immune additives to the animals, to provide a more sterile bedding material, and to inhibit ammonia fumes and odors due to animal waste. It is also desirable that a "ready-to-use" bedding material be provided, thereby eliminating labor-intensive bedding treatment procedures and their inherent facility down-time.
There also exists a need for a method and system capable of applying a sufficient quantity of additives to a paper base material in a manner which causes the additives to adhere to the base material.
A need further exists for a method and system of producing an animal bedding material having good thermal insulating qualities, high absorbency, high surface coverage per unit weight, and high loft in use.
A need also exists for an economical method and system for making an animal bedding material meeting these needs from readily available waste products, thereby reducing the amount of waste to be landfilled.
It is to the provision of a method and system meeting these and other needs that the present invention is directed.